Needle terminal assembly



' June 4, 1957 P. A. STEVENS NEEDLE TERMINAL ASSEMBLY Filed July 31,1952 IN1/12mm Peer A. Sieyens BY Y NEEDLE TERMHNAL ASSEMBLY Peter A.Stevens, Waterbury, Conn.

Application July 31, 1952, Serial N 361,954

Claims. (Cl. usm-214) This invention relates to a ow tube and needleassembly, particularly to the assembly of the blood ow tube with theneedles at the two ends thereof in a blood donor set, although theinvention is not specifically limited to blood donor sets.

A blood donor set includes amongst other things a hypodermic needle forreceiving the douors blood, which needle is connected by a flexible tubeto a piercing needle that delivers the blood into a sterile container.It is one of the -objects of the present invention to provide such aconnection between the tube and the needles that the end of the needlethat is connected to the tube cannot injure the exible tube. This isaccomplished, in the preferred embodiment of the present invention, byproviding a spacer between the very end of the sharp needle and ltheblood ow tube, so that the sharp end of the needle cannot under anycircumstances pierce the tube. The spacer makes a sealing lit around theneedle and also makes a sealing fit within the tube. This permits theuseof a tube of a substantially larger diameter than the diameter of theneedle. The large diameter blood flow tube may be depressed slightly andthen 4released to draw blood for aspiration.

While 'the present invention is concerned, in its most specic aspects,with the connection to piercing needles of the type used in a blooddonor set, in its broader aspects the invention is applicable to themeans for establishing connections with a piercing needle, whether thatis part of a blood donor set or any other type of equipment, moreparticularly, equipment used in the medical arts. By way of example, insome instances there is provided a exible tube which is to be connectedto a needle and which ltube is required to be of a small diameter. Insuch case, also, the principles of the present invention are applicablefor preventing piercing or injury of the liexible tube by the cannula.This may be accomplished by providing the spacer tube on the outside ofthe iiexible ow tube rather than on the inside thereof, so that thespacer tube is between the ilexible tube and the hub of the hypodermicof piercing needle rather than between the flexible tube and the cannulaof the needle. lt is a still Vfurther object of the present invention toprovide means for facilitating securing of a iiexible ow tube within thehub of a needle, even though the flexible ow tube may be comparativelythin.

The attainment of the above and further objects of the present inventionwill be apparent from the following specification taken in conjunctionwith the accompanying drawing forming a part thereof.

In the drawing: j Y

Figure `l is a view, in partial section, of a needle assembly of a blooddonor set; Y

Figure Z is a longitudinal sectional view illustrating a modification ofthe structure of Figure l; and

Figure 3 is a longitudinal sectional view illustrating still anothermodification.

ln the drawing like reference numerals designate like parts throughout.

2,794,435 Fatented June 4, 1957 At 1 there is'shown a portion of a blooddonor set that includes la donor needle assembly 2, a rubber-piercingneedle assembly 3, and a exible tube 4 of Vinylite or other suitablematerial, preferably transparent or semitransparent, connecting the twoneedles for the flow of uid, in this instance blood, from one needle andout through the other. The donor needle assembly 2 includes a cannula 8having a penetrating point 9 at one end thereof, the opposite end 10being squared, namely at right angles to 'the -central longitudinal axisof the lumen of the cannula. The cannula is of stainless steel tubing,in this kinstance having an outside diameter of .058 inch and having alongitudinal bore Vor lumen 11 from end to end therethrough and Vof aninternal diameter of .042 inch. The above gures are merelyillustrativeof one construction. The cannula extends through a hub 12that is swaged thereon. To that effect the hubrhas a Y needle-receivingbore-14 and a connecting counterbore particular construction hereillustrated the outer tube had an internal diameter of .140 inch whereasthe inner tube had an outer diameter of .150 inch, so that the outertube is tensioned by the inner'tube and in turn compresses the innertube.

an internal diameter of .05() inch and fitted over a cannula having anexternal diameter of .058 inch, so that the inner tube was tensioned onand made a snug sealing tit around the cannula., The' portion of theinner tube 20' that extends outwardly of the end 21 of the outer tub'eis inserted into the bore 16 of' the hub until the end 21 of the Aoutertube abuts against the ilange 18. This limits the extent to which thecannula may be inserted into the v- The length of the portion of thecannula proinner tube. jecting beyond the ange 18 is exactly equal tothe distance between the end 21 of the -outer tube and the end 26 of theinner tube, so that when the end of the outer tube abuts against theflange 18 the end 26 of the inner tube is exactly flush with the end 10of the cannula.

The construction of the rubber piercing needle 3 is substantially thesame as that of the donor needle 2. The rubber piercing needle includesa stainless steel cannula 8' having a rubber piercing end V9 on which isswaged a hub 32, said needle extending through a bore 34 in the hubwhich bore 34 opens'into a larger bore 36 that terminates in aperipheral flange 3S. A washer 39 is secured to the hub 32 adjacent tothe flange 38 to facilitate forcing of the rubber piercing point'9 oftheV cannula 8 into and through the plug of rubber or the" like whichcloses a sterilized blood-receiving bottle, preferably evacuated, as iswell known in the art. Thetube 4; has at the rubber piercing needle endthereof an inner tube Ztl of the same size and construction as .waspre-- viously described. secured therein inthe same manner as waspreviously described. The-end 40 of the vcannula 8 terminates flush withthe inner. end of the tube 20. The

end 26 of the tube 20 at the rubber piercing end of the blood donor setis located the required distance from' the adjacent end 21 of the outertube 4 so that when the` end of the tube 4 abuts against the flange 38.By such The two Vinylite tubes are cemented togetherin such a mannerthat the cementingassures an air-'Y tight and liquidtight seal betweenthem. A Vinylite solvent is vone suitable .'cemen'titious material. VInthe construction herein illustrated the inner Atube 2i? wasof abutmentone is apprised of the fact that the end 40 of the needle is liush withthe inner end 26 of the inner tube 20. In this construction, as in thedonor end Yofjthe tube 4, the outside diameter of the cannula (8') isgreater than the inside diameter of the tube 20; In one construction thecannula, of an outside diameter of .072inch, was inserted into a tube 20having an inside diameter of .050 inch, thus stretching the tube 20 andthereby producing a sealing liquid-tight and air-tight t around-theneedle for substantially the full length of the tube 20.

In the construction above described, any flexing of 'the tube 4 ateither end thereof results in compression of part of the wall of thetube 4 at the end 26 of the inner tube but such iiexure cannot possiblybring the outer tube 4 into physical contact with the inserted end ofthe cannula. As a result, there is no danger that the inner end of thecannula can injure the outer tube.

In View of the fact that the plastic tube is inserted directly on thecannula there is assurance of continuous flow directly through thecannula and it is not necessary to solder the hub onto the cannula or totake other precautions to make sure that the hub in either case makesankair-tight sealing t around the periphery of the cannula.

In the construction above described the liquid that flows through theneedles is never in contact with the hubs. As a result, the finish onthe hubs does not have to be-made with the care that would otherwise berequired.

In the arrangement above described there is used a tube 4 of an internaldiameter large in comparison with the external diameter of the cannulawithout. the disadvantage of requiring a liquid-tight, air-tight sealbetween the tube 4 and the hub. The fact that the tube 4 tube 4 issuiciently elastic so that when the tube 4 isV pinched together to stopflow therethrough the elastic limit of the material is not exceeded, sothat upon release of the pinching action the material will spring backto its original shape under its natural resiliency.

It is apparent from the above description that the end 10 of the cannula8 cannot possibly come into contact with the tube 4 regardless of theamount of flexing or bending of the tube at the end thereof. As aresult, it is possible to make the tube 4 of very thin material sincethe danger `of piercing or fracturing of the tube by the cannula hasbeen eliminated. The tube 4 can be maderof as large a diameter as isdesired, it being recognized that a large diameter is advantageous inmany respects.

The length of the cannula within the tube is sutiicient to form anair-tight seal between the tube and the outside of the cannula. This,together with the fact that there is an air-tight seal between the`inner tube 20V and the outer tube 4, assures that no air can bedrawninto the tube 4 from the atmosphere immediately surrounding the hub 12.For this reason there is no necessity for soldering the hub to thecannula as would otherwise be necessary where it is desired to secureY aleak-tight connection between the hub and the cannula. The eliminationvof soldering also reduces the danger of corrosion.

In Figure 2 there is shown a modified construction of the donor'needleassembly Vor ofl the piercing needle. as-

sembly. In this case, as before, the blood flow tube is indicated at 4,being made of plastic (or rubber) as previously described. In thisconstruction the inner Vinylite tube isindicated at 42, that tubecorresponding to the tube 20 of Figure l and differing therefrom only inthat it is of shorter length so that the end 43 thereof terminates flushwith the end 21 of the tube 4. The cannula 8 has a hub 45 securedthereto in any desired manner, the cannula extending through the bore 14thereof and through the counterbore 16'. This counterbore differs fromthe counterbore 16 essentially only in that it is of larger diameter, adiameter sufiicient to receive the end of the tube 4, whichtube makes asnug sliding tit therein. Y The cylindrical wall 47 of the hub may bepinched radially inwardly to assure locking of the tube 4 within thehub. In this construction the tube 42 may be longer than the bore 16',or of a length equal to the length of the bore 16', or shorter than thebore 16'. In this construction, as in the construction of Figure l,there is the advantage of using a tube 4 of a diameter appreciablylarger than the external diameter of the cannula. In this structure theblood or other luid flowing through the tube 4 cannot possibly come incontact with the hub and the thin flexible tube 4 is safe against beingtorn or injured by the end of the stainless steel cannula.

In Figure 3 there is shown a modied construction that i is somewhatsimilar to the construction of Figure 2 but differs therefrom in thathere the tube 50, that corresponds to the tube 42 of Figure 2, is on theoutside of the blood flow tube 4 rather than on the inside thereof. Insome types of medical apparatus it is desirable to use a small diameterflow tube 4 through which blood or other iiuid flows. When this is thecase the tube 50,`which is sealed on the outside of the tube 4' to forma liquid-tight, airtight seal, provides the necessary thickness at thebore 16 so that the wall 47 of the hub may be pinched tight onto theinserted tube end and permit the use of a thin walled tube 4 whereotherwise a larger thickness tube might be called for.

The assembled unit of Figures l, 2, or 3 must, of course, be sterilized.This may be accomplished in any desired manner, heat sterilization beingone approved method. When a Vinylite tube which is under tension issubjected to the heat of sterilization it may stretch suciently toovercome the tension.' The tubes 26 of Figure 1 being cement sealedwithin the tube 4 of Figure 1 maintain an air-tight seal between them,regardless of the tension of the tube 4. Likewise, for that same reason,the two Vinylite tubes 4 and 42 of Figure 2 and 4' and 5l) of Figure 3may be cement sealed together to Vform air-tightV statutes I have hereshown and described a few preferredV embodiments of my invention. It is,however,. to be understood that the invention is not limited to theprecise constructions here shown, the same being merely illustrative ofthe principles of the invention. Whatl consider new and desire to secureby Letters Patent is:

1. In a medical apparatus including a exible tube terminating in aneedle having a cannula with a lumen therethrough, a part of the cannulabeing telescoped into the tube, means for inhibiting injury of the tubeby the end of the cannula therein, said means comprising an auxiliarytube of flexible material within the end of the first tube andsurrounding the end of the cannula that is within the first tubeandterminating within the rst tube ush with the surrounded end of thecannula, and a hub secured to the cannula and having a bore intoV whichone of said tubes extends and makes a snug tit.

2. In a medical apparatus including a liexible tube terminating in aneedle having a cannula with a lumen therethrough, a part of the cannulabeing telescoped into the tube, means for inhibiting injury of the tubeby the end of the cannula therein, said means comprising an auxiliarytube of iexible material within the end of the first tube andsurrounding the end of the cannula that is Within the rst tube andterminating Within the rst tube flush with the surrounded end of thecannula, the auxiliary tube making an air-tight lit around the cannulaand an air-tight fit within the rst tube, and a hub secured to thecannula, said hub being in telescoping relationship with at least one ofthe tubes and being sealed from the path of flow through the lumen bythe air-tight tit hereinabove referred to.

3. In a medical apparatus including a flexible tube terminating in aneedle having a cannula with a lumen therethrough, a part of the cannulabeing telescoped into the tube, means for inhibiting injury of the tubeby the end of the cannula therein, said means comprising an auxiliarytube of flexible material within the end of the rst tube and surroundingthe end of the cannula that is within the rst tube and terminatingwithin the rst tube flush with the surrounded end of the cannula, theauxiliary tube making an air-tight fit around the cannula and anair-tight v fit within the rst tube and extending outwardly of the firsttube, and a hub for the cannula, said hub having a bore into which theauxiliary tube makes a snug fit, and the end of the first tube abuttingagainst the hub.

4. In a medical apparatus including a flexible tube terminating in aneedle having a cannula with a lumen therethrough, a part of the cannulabeing telescoped into the tube, an auxiliary tube of flexible materialwithin the end of the rst tube and surrounding the end of the cannulathat is within the first tube, the auxiliary tube making an air-tightfit around the cannula and an air-tight fit within the first tube andextending outwardly of the first tube, and a hub for the cannula, saidhub having a bore into which the auxiliary tube makes a snug t.

5. In a medical apparatus including a exible tube terminating in aneedle having a cannula with a lumen therethrough, a part of the cannulabeing telescoped into the tube, an auxiliary tube of flexible materialwithin the end of the first tube and surrounding the end of the cannulathat is within the rst tube, the auxiliary tube making an air-tight taround the cannula and an air-tight fit within the first tube, and a hubfor the cannula, said hub having a bore into which one of the tubesmakes a snug fit.

6. In a medical apparatus including a flexible tube terminating in aneedle having a cannula with a lumen therethrough, a part of the cannulabeing telescoped into the tube, an auxiliary tube of flexible materialwithin the end of the rst tube and surrounding the end of the cannulathat is within the first tube, the auxiliary tube making an air-tightfit around the cannula and an air-tight t within the rst tube andextending outwardly of the first tube, and a hub for the cannula, saidhub having a bore into which the auxiliary tube makes a snug t, said rsttube being transparent and suciently resilient to permit manual pinchingof the same to stop flow therethrough without exceeding the elasticlimit of the material thereof.

7. In combination, a cannula, a hub secured to the cannula, a firstflexible tube surrounding the cannula and terminating flush with one endthereof and extending into the hub, and a second flexible tubesurrounding the rst tube and extending from an intermediate portion ofthe first tube to and beyond said end of the cannula.

8. In combination, a cannula, a hub secured to the cannula intermediateits ends, a first flexible tube surrounding the cannula yand terminatingflush with one end of the cannula, and a second flexible tubesurrounding the first tube and extending from the hub to `and beyond theend of the cannula, the first tube making a sealing t with the cannulaand with the second tube.

9. ln combination, a cannula having a pointed penetrating end andsquared at its opposite end, a hub secured to the cannula intermediateits ends, a first flexible tube surrounding the cannula and terminatingush with the squared end and extending into the hub, and ta secondexible tube surrounding the rst tube and extending from the hub to andbeyond the squared end of the cannula.

l0. In a blood donor set of the type that includes a donor needleassembly for receiving blood from a donor and a piercing needle assemblyfor delivering the blood to an evacuated receptacle :and a flexible tubeconnecting the two assemblies, at least one of the assemblies includinga cannula; means for making an air-tight seal between the cannula andthe tube and preventing injury of the tube by the end of the cannulaupon flexing of the tube, said means comprising a second tube extendingaxially into the first tube and making an air-tight t therewith, saidcannula extending axially into the second tube and terminating thereinush with that end thereof which is within the first tube and said secondtube being tensioned around the cannula and making an air-tight sealingfit therewith, and a hub on the cannula intermediate the ends thereof,said hub having a bore into which the second tube extends, the cannulaprojecting outwardly of the hub an amount equal to the amount that thesecond tube extends into the first tube, the end of the rst tubeabutting against the hub.

References Cited in the file of this patent UNITED STATES PATENTS1,839,338 Pentz Jan. 5, 1932 2,589,426 Ogle Mar. 18, 1952 2,638,897Poitras May 19, 1953 2,689,563 Huber Sept. 21, 1954 2,689,564 Adams etal Sept. 21, 1954 2,702,037 Walter Feb. 15, 1955 2,716,982 Ryan Sept. 6,1955

